NEW YORK (AP) — Imagine gathering nearly everything that has rattled investors’ nerves over the past four years: the European debt crisis, fights over the U.S. government’s budget and moves by the Federal Reserve. Now imagine all of them crammed into one month.

As August wrapped up, trading desks and investment firms looked warily at the lineup of events slated for September and warned clients of turbulence ahead.

The Fed’s September meeting is when many on Wall Street think the central bank will begin winding down its massive bond-buying program. German voters will decide whether Chancellor Angela Merkel gets another term as the leader of Europe’s largest economy. And Congress will be on a tight deadline to pass a spending bill before the month ends, a process which could easily turn into another brawl over raising the government’s borrowing limit.

Each item on the calendar could cause big swings in daily trading. And collectively, they could make an often dangerous month for the market even more volatile.

Then there is the wildcard. President Barack Obama on Saturday said that the U.S. should take military action in response to the alleged use of chemical weapons in an attack that killed hundreds in Syria.

Obama, however, said that he would seek congressional approval before any military strike. Congress is scheduled to reconvene Sept. 9.